package com.itheima.reggie.controller;

import com.itheima.reggie.common.R;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;


/**
 * 文件上传下载
 */
@RestController
@RequestMapping("/common")
public class CommonController {

    @Value("${reggie.path}")
    private String basePath;


    /**
     * 文件上传
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public R upload(MultipartFile file) {

        //获取原始文件名
        String originalFilename = file.getOriginalFilename();
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));


        //使用UUID重新随机生成文件名
        String fileName = UUID.randomUUID().toString() + suffix; //dasdadssd.jpg

        //创建一个目录对象
        File dir = new File(basePath);
        //判断当前目录是否存在
        if (!dir.exists()){
            //不存在，创建目录
            dir.mkdirs();
        }


        try {
            //将临时文件转存到指定位置
            file.transferTo(new File(basePath + fileName));  //路径+文件名  C:\img\  +  dasdadssd.jpg
        } catch (IOException e) {
            e.printStackTrace();
        }


        return R.success(fileName);

    }


    /**
     * 文件下载
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void downLoad(String name, HttpServletResponse response){


        //输入流，通过输入流读取文件内容
        try {
            //输入流，通过输入流读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath + name));
            //输出流，通过输出流将文件写回到浏览器，在浏览器展示图片
            ServletOutputStream outputStream = response.getOutputStream();

            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = fileInputStream.read(bytes)) != -1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }

            //关闭资源
            outputStream.close();
            fileInputStream.close();


        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
